[ADSx] - HashFun

import java.util.Map;
import java.util.Scanner;

public class HashFun {
    public static void main(String args[]) {
        String text = "24\n" +
                "Mila 19.6.1989\n" +
                "Ivana 19.6.1977\n" +
                "Simon 19.6.1994\n" +
                "Ognen 19.6.1998\n" +
                "Leona 19.6.1999\n" +
                "Martin 19.6.1981\n" +
                "Vesna 13.4.2015\n" +
                "Katerina 12.3.1945\n" +
                "Milan 14.2.1996\n" +
                "Olja 13.2.1988\n" +
                "Bojan 19.6.1988\n" +
                "Bojan 19.7.1978\n" +
                "Bojan 19.7.1988\n" +
                "Bojana 19.6.1988\n" +
                "Bojan 21.6.1988\n" +
                "Bojan 22.7.1988\n" +
                "Bojan 24.7.1988\n" +
                "Bojan 27.7.1988\n" +
                "Ana 19.7.1987\n" +
                "Bojana 19.6.1988\n" +
                "Elena 1.1.1988\n" +
                "Filip 1.12.1988\n" +
                "Filip 2.11.1976\n" +
                "Elena 13.1.1966\n" +
                "6";

        Scanner scanner = new Scanner(text);
        int numOfPeople = Integer.parseInt(scanner.nextLine());

        // Month -> List of Names
        CBHT<Integer, String> map = new CBHT<>(12);
        for (int i = 0; i < numOfPeople; i++) {
            String[] split = scanner.nextLine().split("\\s+");
            String name = split[0];
            Integer month = Integer.parseInt(split[1].split("\\.")[1]);

            map.insertLast(month, name);
        }

        Integer target = Integer.parseInt(scanner.nextLine());

        SLLNode<MapEntry<Integer, String>> current = map.searchList(target);

        System.out.println();
        System.out.println(map);

        if (current == null) {
            System.out.println("Nema");
            return;
        }

        while (current != null) {
            System.out.print(current.element.value + " ");
            current = current.succ;
        }

        // deleteFirst a whole SLL at a certain key

        System.out.println("=====================");
        map.deleteEntry(6, "Mila");

        System.out.println();
        System.out.println(map);


    }
}

class SLLNode<E> {
    protected E element;
    protected SLLNode<E> succ;

    public SLLNode(E elem, SLLNode<E> succ) {
        this.element = elem;
        this.succ = succ;
    }

    @Override
    public String toString() {
        return element.toString();
    }
}

class MapEntry<K extends Comparable<K>, V> implements Comparable<K> {

    // Each MapEntry object is a pair consisting of a key (a Comparable
    // object) and a value (an arbitrary object).
    K key;
    V value;

    public MapEntry(K key, V val) {
        this.key = key;
        this.value = val;
    }

    public int compareTo(K that) {
        // Compare this map entry to that map entry.
        @SuppressWarnings("unchecked")
        MapEntry<K, V> other = (MapEntry<K, V>) that;
        return this.key.compareTo(other.key);
    }

    public String toString() {
        return "<" + key + "," + value + ">";
    }
}

class CBHT<K extends Comparable<K>, V> {

    // An object of class CBHT is a closed-bucket hash table, containing
    // entries of class MapEntry.
    private SLLNode<MapEntry<K, V>>[] buckets;

    @SuppressWarnings("unchecked")
    public CBHT(int m) {
        // Construct an empty CBHT with m buckets.
        buckets = (SLLNode<MapEntry<K, V>>[]) new SLLNode[m];
    }

    private int hash(K key) {
        // Translate key to an index of the array buckets.
        return Math.abs(key.hashCode()) % buckets.length;
    }

    public SLLNode<MapEntry<K, V>> search(K targetKey) {
        // Find which if any node of this CBHT contains an entry whose key is
        // equal
        // to targetKey. Return a link to that node (or null if there is none).
        int b = hash(targetKey);
        for (SLLNode<MapEntry<K, V>> curr = buckets[b]; curr != null; curr = curr.succ) {
            if (targetKey.equals(curr.element.key)) return curr;
        }
        return null;
    }

    public void insert(K key, V val) {        // Insert the entry <key, val> into this CBHT.
        MapEntry<K, V> newEntry = new MapEntry<K, V>(key, val);
        int b = hash(key);
        for (SLLNode<MapEntry<K, V>> curr = buckets[b]; curr != null; curr = curr.succ) {
            if (key.equals(((MapEntry<K, V>) curr.element).key)) {
                // Make newEntry replace the existing entry ...
                curr.element = newEntry;
                return;
            }
        }
        // Insert newEntry at the front of the 1WLL in bucket b ...
        buckets[b] = new SLLNode<MapEntry<K, V>>(newEntry, buckets[b]);
    }

    public void insertFirst(K key, V val) {
        MapEntry<K, V> entry = new MapEntry<>(key, val);
        int b = hash(key);
        /**
         * Prepending an element in the SLL */
        SLLNode<MapEntry<K, V>> insert = new SLLNode<>(entry, buckets[b]);
        buckets[b] = insert;
    }

    public void insertLast(K key, V val) {
        MapEntry<K, V> entry = new MapEntry<>(key, val);
        int b = hash(key);
        /**
         * Append an element in the SLL */
        if (buckets[b] != null) {
            SLLNode<MapEntry<K, V>> insert = new SLLNode<>(entry, null);
            SLLNode<MapEntry<K, V>> current = buckets[b];
            if (current.element.value.equals(val)) return;
            while (current.succ != null) {
                if (current.element.value.equals(val)) return;
                current = current.succ;
            }
            if (current.element.value.equals(val)) return;
            current.succ = insert;
        } else {
            insertFirst(key, val);
        }
    }

    public SLLNode<MapEntry<K, V>> searchList(K targetKey) {
        int b = hash(targetKey);
        return buckets[b];
    }

    public void deleteFirst(K key) {
        // Delete the entry (if any) whose key is equal to key from this CBHT.
        int b = hash(key);
        for (SLLNode<MapEntry<K, V>> pred = null, curr = buckets[b]; curr != null; pred = curr, curr = curr.succ) {
            if (key.equals(curr.element.key)) {
                if (pred == null)
                    buckets[b] = curr.succ;
                else
                    pred.succ = curr.succ;
                return;
            }
        }
    }

    public void deleteLast(K key) {
        int b = hash(key);
        SLLNode<MapEntry<K, V>> current = buckets[b];
        SLLNode<MapEntry<K, V>> successor = buckets[b].succ;
        while (successor.succ != null) {
            current = current.succ;
            successor = successor.succ;
        }
        current.succ = null;
    }

    public void deleteSLL(K key) {
        int b = hash(key);
        buckets[b] = null;
    }

    public void deleteEntry(K key, V val) {
        MapEntry<K, V> entry = new MapEntry<>(key, val);
        int b = hash(key);

        SLLNode<MapEntry<K, V>> previous = buckets[b];
        SLLNode<MapEntry<K, V>> current = buckets[b].succ;
        SLLNode<MapEntry<K, V>> successor = buckets[b].succ.succ;

        if (previous.element.value.equals(val)) {
            deleteFirst(key);
            return;
        }

        while (current.succ != null) {
            if (current.element.value.equals(val)) {
                previous.succ = current.succ;
            }

            previous = previous.succ;
            current = current.succ;
            successor = successor.succ;
        }

        if (current.element.value.equals(val)){
            previous.succ = null;
        }

    }

    public String toString() {
        StringBuilder temp = new StringBuilder();
        for (int i = 0; i < buckets.length; i++) {
            temp.append(i).append(":");
            for (SLLNode<MapEntry<K, V>> curr = buckets[i]; curr != null; curr = curr.succ) {
                temp.append(curr.element.toString()).append(" ");
            }
            temp.append("\n");
        }
        return temp.toString();
    }

}